Wedge shaped driving belt



May 12, 1931. L. wALLFlscH xix M Patented May '12, 1931 PATENT OFFICELUDWIG WALLIISCH, OF momma, GERMANY WEJGE SHAPED DRIVING BELTApplication filed December- 14, 1929, Serial 1T0. 414,178, and inGermany December 14, 1988;

This invention relates to a wedge-shaped driving belt for powertransmission. In comparison withthe driving belts of known constructionthe belt according to the inven- 5 tion is of H-sh'aped cross section,so that the belt has two upper and two lower side flaps which, when the.belt is moving around the corresponding belt pulley, bear tightlyagainst the walls of the pulley owing to the curvature of this pulley,the upper flaps in outward direction and the lower flaps in inwarddirection. The belt pulley must, with this object in view, also be ofwedge-shaped cross section so that it has an inner projecting beadagainst the side faces of which the inner faces of the lower side flapsof the belt can bear. As experiments have shown, such driving belt ofH-shaped cross section is much more effective than a wedge-shaped beltof solid cross section or than a wedgeshaped belt with only one lower orupper groove.

' Two embodiments of the invention are illustrated by way of example inthe accom- 25, panying drawings in which:

Fig. 1 shows in cross section a belt pulley with belt according to theinvention.

Fig. 2 is a. similar view showing a belt pulle and belt of modifiedform.

eferring to Fig. 1 the wedge-shaped belt a has a groove 6 in the upperside and a groove 0 in the lower side, said grooves extending in thedirection of the longitudinal axis of the belt.

Owing to these grooves b and a the belt is of H-shaped cross-section andtwo upper side flaps (Z and (Z and two lower side flaps e and 0 areformed. The belt pulley f is shaped as shown, i. e. it is ofwedge-shaped cross section with two outer side walls 9 and g and aprojecting bead h on the rim.

Owing to the curvature of the belt on the circumference of the pulleythe upper side flaps (Z and d of the belt are pressed in outwarddirection against the inner surfaces of the side walls 9 and 9 of thepulley, whereas the inner surfaces of the lower side flaps e, and 0 arepressed against the outer surfaces of the bead h of the pulley.

The form of construction shown in Fig. 2

differs from that shown in Fig.1 thereby that the wedge-shaped belt has,besides the side flaps, a central rib 2' designed to engage with acorresponding groove is in the circumference of the belt pulley. Morethan one rib and groove may be provided.

The lower surface of the driving belt mounted on the belt pulley must bea certain distance from the circumference of the belt pulley so thatsuflicient clearance exists to compensate for wear.

I claim p A wedge-shaped driving belt for power transmission which is ofH-shaped cross section having two upper and two lower side flaps so thatowing to the curvature of the belt around the belt pulley the upper sideflaps bear against the pulley. with their outer surface and the lowerside flaps with their inner surface.

In testimony whereof I afiix mysignature.

LUDWIG WALLFISCH.

